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Around the world, twice a day, everyday, more than 700 weather balloons launch into the air. 14 of those balloons are released across Alaska, tracking things like temperature, humidity and wind speed.Listen nowWilliam Wells releases a weather balloon on Alaska’s St. Paul Island. (John Ryan photo)They provide a wealth of information for people like Brian Brettschneider, a climatologist in Anchorage. Alaska’s Energy Desk is checking in with him regularly as part of a new segment, Ask A Climatologist.This week, Brettschneider is responding to a question from a listener named Dennis who asked why surface winds can sometimes be traveling in the opposite direction of winds several thousand feet up.Interview transcriptBrian: The listener is correct that they can very often be coming from different directions. I looked at the weather balloon reports yesterday from Anchorage and winds at the surface were coming from the southeast and from several thousand feet up, coming from the Northeast. There are a couple of good reasons for that. It’s actually much more pronounced in the wintertime, but the conditions that drive the winds at the upper levels can be in many cases quite a bit different than what’s going on at the surface.Annie: And weather balloons are the best way to capture these differences?Brian: Yes, the weather balloon program has gone on since 1948, and it’s an important snapshot in time. So the weather balloon’s the gold standard for those types of observations.Annie: And we have a lot of them in Alaska.Brian: Right, we have 14. They ring the coastline and there’s a couple in the interior and they launch twice a day at the exact same time. About 750 to 800 globally all release their balloons at the exact same time, so it’s really important to have that snapshot in time of what’s going on in the atmosphere.Annie: And as a climatologist, how much attention do you pay to what’s going on with these balloons?Brian: I think it’s fascinating. From an operation point of view, the meteorologists, the forecasters at the National Weather Service, they play very close attention to how the weather balloon data looks. From a climatological point of view, it’s also very important. So I was able to look at them historically, and look at, say, the amount of moisture in the air, or the temperatures at 5,000 feet. And again sometimes what goes on at the surface kind of masks what the general state of the atmosphere is.We see that particularly in winter. We can have a very warm air mass at five or ten thousand feet but we have a little bubble of cold air stuck over us at the surface. So in reality, it’s a warm air mass, but we don’t even know it. Without that weather balloon, we would have no idea.Annie: What happens to the balloons?Brian: With the low pressure at tens of thousands of feet up, the balloon pops, it has a little parachute, and it slowly makes its way back down to the earth. It has some instructions on it, for if someone finds it, how to return it- they can be refurbished. Here in Alaska, almost none are ever found. In part because most of our stations are along the coast and there’s a high probability that they fall in the water.A friend of mind actually did find one this summer, in the Chugach mountains, in an isolated spot. That was an uncommon event. I believe less than one percent of the balloons launched in Alaska are ever found. But they’re a very important piece of the climatological puzzle for Alaska.read more